How to update the data in listview in Xamarin.Forms?

First you add a new class as a ViewModel like:

public class RoomViewModel : BaseViewModel
{
   [here following code]
}

If you don’t have BaseViewModel try to download from nuget Refractored.MvvmHelpers. Then in your class define an observable collection like

  public ObservableCollection<RoomRecommandation> _roomSuggestionList = 
               new ObservableCollection<RoomRecommandation>();
  
  public ObservableCollection<RoomRecommandation> Recommendations
  {
     get { return _roomSuggestionList; }
  }

In your ContentPage add a listview like:

<ListView ItemsSource="{Binding Recommendations}">
 <ListView.ItemTemplate>
   <DataTemplate>
     <ViewCell>
       <Grid Padding="10" RowSpacing="10" ColumnSpacing="10">
         <Grid.RowDefinitions>
           <RowDefinition Height="" />
         </Grid.RowDefinitions>
         <Grid.ColumnDefinitions>
           <ColumnDefinition Width="Auto" />
           <ColumnDefinition Width="" />
           <ColumnDefinition Width="Auto" />
         </Grid.ColumnDefinitions>
         <controls:CircleImage Grid.Column="0" BorderColor="#DDD3CB" 
                               BorderThickness="3" WidthRequest="66"
                               HorizontalOptions="CenterAndExpand" 
                               VerticalOptions="CenterAndExpand" 
                               Aspect="AspectFill" 
                               Source="{Binding Image}" />
         <Label Grid.Column="1" Text="{Binding Description}" 
                               VerticalOptions="Start" />
         <Label Grid.Column="2" Text="{Binding Price, StringFormat='£{0}'"
                               FontSize="Small" VerticalOptions="Start" />
        </Grid>
      </ViewCell>
    </DataTemplate>
  </ListView.ItemTemplate>
 </ListView>

Then in your ContentPage code:

  RoomViewModel vm = null;
  public RoomPage ()
  {
      InitializeComponent ();
      LoadData();
  }

  public void LoadData()
  {
      if (vm == null)
      {
          vm = new RoomViewModel();
          BindingContext = vm;
      }
  }

Happy coding!